1. Field of the Invention
The present invention relates to a backlight unit; and, more particularly, to a backlight unit including fixing members capable of preventing movement of a plurality of divided light guide panels.
2. Description of the Related Art
A liquid crystal display has many advantages such as implementation of weight reduction, thickness reduction, low-power driving and high resolution. Therefore, nowadays, a display has been replaced from a cathode-ray tube to the liquid crystal display.
The liquid crystal display includes a backlight unit and a liquid crystal panel which are coupled to each other. The backlight unit generates light in order to supply the light to the liquid crystal panel. The liquid crystal panel includes a liquid crystal panel for displaying an image by adjusting transmittance of the light supplied from the backlight. Such a liquid crystal display implements a high quality image by uniformly supplying high brightness light of the backlight unit to the liquid crystal panel.
Herein, the backlight unit requires high power to generate the light having the high brightness, which increases power consumption of the liquid crystal display.
In order to solve the problem, a local dimming driving method of the backlight unit has been developed to supply light with partially adjusted brightness to the liquid crystal panel. A structure of the backlight unit employing the local dimming method includes a plurality of divided groups. Herein, each of the groups includes one or two or more divided light guide panels and light sources which are arranged at one side of each of the light guide panels. At this time, the backlight unit employing the local dimming method generates light with brightness values adjusted by the groups in order to partially supply the light to the liquid crystal panel. That is, some groups of the backlight unit corresponding to some portions of a screen which are displayed brightly generate light with high brightness and the other groups of the backlight unit corresponding to the other portions of the screen generate light with low brightness or are turned off.
Therefore, if the liquid crystal display partially requires high brightness, it is possible to partially drive the backlight unit, thereby reducing power consumption of the backlight unit. In addition, the backlight unit implementing the local dimming driving method can partially control the brightness, thereby improving a contrast ratio of the liquid crystal display.
However, since the backlight unit employing the local dimming driving method has the plurality of divided light guide panels, there are caused many problems due to movement of the light guide panels, for example, generation of noise, deterioration of an image quality characteristic of the liquid crystal display and damage of an optical sheet arranged at upper portions of the light guide panels due to the movement of the light guide panels.